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  <title>简介</title>

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  <h1 class="title">简介</h1>
  <p class="simpara">
   These functions allow you to work with arbitrary-length integers
   using the GNU <acronym title="Multiple Precision">MP</acronym> library.
  </p>
  <p class="simpara">
   These functions have been added in PHP 4.0.4. 
  </p>
  <blockquote class="note"><p><strong class="note">Note</strong>: 
   <p class="para">
    Most GMP functions accept GMP number arguments, defined as
    <em>resource</em> below. However, most of these
    functions will also accept numeric and string arguments, given
    that it is possible to convert the latter to a number. Also, 
    if there is a faster function that can operate on integer arguments,
    it would be used instead of the slower function when the supplied arguments are
    integers. This is done transparently, so the bottom line is that
    you can use integers in every function that expects GMP
    number. See also the <span class="function"><a href="function.gmp-init.html" class="function">gmp_init()</a></span> function.
   </p>
  </p></blockquote>
  <div class="warning"><strong class="warning">Warning</strong>
   <p class="simpara">
    If you want to explicitly specify a large integer, 
    specify it as a string. If you don&#039;t do that, PHP will
    interpret the integer-literal first, possibly resulting
    in loss of precision, even before <em>GMP</em> 
    comes into play.
   </p>
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  <blockquote class="note"><p><strong class="note">Note</strong>: 
   <span class="simpara">
    This extension is available on Windows platforms since PHP 5.1.0.
   </span>
  </p></blockquote>
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